Battery

Abstract

The battery comprises a battery shell and a battery cover plate assembly, a battery cell is placed in the battery shell, the battery cover plate assembly is connected to an opening in the top end of the battery shell, the battery cover plate assembly comprises a cover plate main body, a pressure relief hole is formed in the cover plate main body, a protruding part is arranged on the periphery of the pressure relief hole, and the protruding part is connected with the battery shell. An anti-explosion piece is arranged in the pressure relief hole and arranged at the position lower than the upper surface of the cover plate body and higher than the lower surface of the cover plate body. According to the battery disclosed by the utility model, the accommodating gap of the electrolyte is increased, and the injection amount of the electrolyte is increased, so that the lithium ion transmission is smoother, and the risk of abnormal opening of the anti-explosion sheet is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to energy storage device technical field, especially relates to a battery. BACKGROUND

[0002] Lithium battery is widely used in electric vehicle, standby power system, microgrid energy storage system with its high energy density, long life and other advantages. Due to a series of chemical reactions inside lithium battery, electrolyte decomposition can produce a large amount of gas, resulting in the internal pressure of the cell. For safety considerations, the battery needs to be provided with a pressure relief mechanism for releasing the heat inside the battery shell when the battery is out of control, but the setting of the pressure relief mechanism causes the limited space inside the battery shell, and the risk of abnormal explosion of the pressure relief mechanism increases. SUMMARY

[0003] Therefore, the utility model provides a battery, increases the accommodation gap of electrolyte, increases the injection amount of electrolyte, makes lithium ion transmission more smooth, reduces the risk of abnormal opening of the rupture disc.

[0004] To achieve the above object, the utility model provides the following technical scheme:

[0005] A battery, comprising a battery shell and a battery cover plate assembly, the battery shell is placed in the cell, the battery cover plate assembly is connected to the top opening of the battery shell, the battery cover plate assembly comprises a cover plate body, the cover plate body is provided with a pressure relief hole, the pressure relief hole is provided with a convex part, the pressure relief hole is provided with a rupture disc, the rupture disc is arranged at a position lower than the upper surface of the cover plate body and higher than the lower surface of the cover plate body.

[0006] From the above technical scheme, the battery provided by the utility model is arranged at a position lower than the upper surface of the cover plate body and higher than the lower surface of the cover plate body in the pressure relief hole, compared with the setting of the rupture disc at one end of the explosion-proof hole close to the cell in the prior art, the setting height of the rupture disc of the utility model is higher, and the distance from the cell is farther, the volume of the cell accommodating cavity of the battery shell is increased, and the accommodation gap of electrolyte is increased. At the same time, the rupture disc is arranged below the upper surface of the cover plate body, even if the convex part is collided by the outside, the deformation of the convex part will not directly affect the connection position of the rupture disc and the pressure relief hole, and the reliability of the rupture disc connection is improved. Due to the increase of the volume of the cell accommodating cavity, the injection amount of electrolyte can be increased, so that the lithium ion transmission is more smooth, and the lithium precipitation in the negative electrode is not easy to occur, the service life of the battery is prolonged, and the space of the cell accommodating cavity is increased, the accommodation space of the gas generated during charging and discharging is expanded, the pressure is not abnormally large when there is less gas in the battery, and the risk of abnormal opening of the rupture disc is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0007] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0008] Figure 1 A schematic diagram of the battery cover assembly provided in an embodiment of this utility model from one angle;

[0009] Figure 2 A schematic diagram of the battery cover assembly provided in an embodiment of this utility model from another angle;

[0010] Figure 3 for Figure 2 A schematic diagram of the cross-sectional structure at position AA in the middle;

[0011] Figure 4 A schematic diagram showing the positions of the explosion-proof valves of the battery cover assembly provided in an embodiment of this utility model, including parameters H1 and H2.

[0012] Figure 5 A partially enlarged structural diagram of the first and second ring trusses provided for embodiments of this utility model;

[0013] Figure 6 A partially enlarged structural schematic diagram of the first ring stage, the second ring stage, and the third ring stage provided in an embodiment of this utility model;

[0014] Figure 7 A schematic diagram of the structure of the explosion-proof sheet provided in this embodiment of the present invention, showing that the upper surface of the sheet is lower than the platform of the first ring platform;

[0015] Figure 8 A schematic diagram of the structure of the explosion-proof sheet provided in this embodiment of the present invention, showing that the upper surface of the sheet is higher than the platform of the first ring platform;

[0016] Figure 9 A schematic diagram showing the structure in which the upper surface of the explosion-proof sheet provided in this embodiment of the present invention is flush with the platform of the first ring platform;

[0017] Figure 10 This is a schematic diagram of the structure of the explosion-proof sheet provided in the embodiment of this utility model;

[0018] Figure 11 for Figure 10 A cross-sectional view of the BB position;

[0019] Figure 12 for Figure 11 A magnified schematic diagram of a portion of the structure.

[0020] Wherein:

[0021] 1, cover plate body,

[0022] 101, protruding part, 102, first ring table, 103, connecting side, 104, third ring table, 105, second ring table,

[0023] 2, L-shaped adapter,

[0024] 3, protective patch,

[0025] 4, pole,

[0026] 5, liquid injection hole,

[0027] 6, explosion-proof sheet,

[0028] 601, connecting table, 602, groove, 603, main patch body,

[0029] 7, pressure relief hole,

[0030] 8, insulating plate,

[0031] 9, negative plate. DETAILED DESCRIPTION

[0032] The utility model discloses a battery, increase the accommodation gap of electrolyte, increase the injection amount of electrolyte, make lithium ion transmission more smooth, reduce the risk of abnormal opening of explosion -proof sheet.

[0033] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the ordinary skilled in the art without creative labor belong to the protection scope of the utility model.

[0034] Referring to Figures 1 to 4 The battery of the utility model, including battery shell and battery cover plate assembly, the electric core is placed in the battery shell, the battery cover plate assembly is connected in the top opening of the battery shell, the battery cover plate assembly includes cover plate body 1, the cover plate body 1 is provided with pressure relief hole 7, the pressure relief hole 7 is provided with protruding part 101 around, the pressure relief hole 7 is provided with explosion -proof sheet 6, the explosion -proof sheet 6 is arranged in the position lower than the upper surface of cover plate body 1, higher than the lower surface of cover plate body 1. The weak part is arranged on the explosion -proof sheet 6, and the weak part is used to release the heat inside the battery when the battery thermal runaway.

[0035] The cover plate body 1 is provided with a liquid injection hole 5.

[0036] The battery of the utility model, through setting the explosion-proof sheet 6 in the position lower than the upper surface of the cover plate body 1 and higher than the lower surface of the cover plate body 1 in the pressure relief hole 7, relative to the prior art of setting the explosion-proof sheet in the explosion-proof hole close to the one end of the battery cell, the setting height of the explosion-proof sheet 6 of the utility model is higher, and the distance from the battery cell is farther, the volume of the battery cell accommodating cavity of the battery shell is increased, and the accommodation gap of the electrolyte is increased.

[0037] The distance between the explosion-proof sheet 6 and the negative plate 9 of the battery cell is H1, the distance between the upper surface of the cover plate body 1 and the explosion-proof sheet 6 is H2, and the range of H1 / H2 is 1.5-15.If the value of H1 / H2 is too small, the distance between the explosion-proof sheet 6 and the negative plate 9 is small, which will affect the gas storage space inside the battery; if H1 / H2 is too large, the distance between the explosion-proof sheet 6 and the upper surface of the cover plate body 1 is small, when the convex part 101 is impacted by the outside, the connection between the explosion-proof sheet 6 and the pressure relief hole 7 will be affected, which will cause the connection reliability of the explosion-proof sheet 6 to be reduced, and the burst pressure of the battery will be affected.

[0038] In an embodiment, the hole wall of the pressure relief hole 7 is provided with a first ring platform 102 and a second ring platform 105, as shown in Figure 5 The first ring platform 102 and the second ring platform 105 are perpendicular to the center line of the pressure relief hole 7, the first ring platform 102 is higher than the second ring platform 105, the first ring platform 102 and the second ring platform 105 are connected by a connecting side surface 103, and the explosion-proof sheet 6 is connected to at least the connecting side surface 103.

[0039] The first ring table 102 is arranged below the upper surface of the cover plate body 1 to avoid damage to the cover plate body 1 and the rupture disc 6.

[0040] Further, as shown in Figure 6 , the third ring table 104 is arranged on the hole wall of the pressure relief hole 7, and the third ring table 104 is lower than the second ring table 105. When the third ring table 104 covers the hole section of the pressure relief hole 7, a plurality of first air holes are arranged on the third ring table 104, the first air holes penetrate the table surface of the third ring table 104, and are used for the gas flow in the battery. The third ring table 104 can be an integral structure with the cover plate body 1, or can be a separate structure, which is not limited here. Specifically, the first air holes are arranged in multiple, and the multiple first air holes are uniformly distributed on the third ring table 104, so as to facilitate the smooth passage of the gas in the battery shell. By arranging the third ring table 104, the lowest arrangement position of the rupture disc 6 is limited, the distance between the rupture disc 6 and the negative plate 9 is increased, and the exhaust space inside the shell is increased.

[0041] In order to improve the insulation performance, the surface of the cover plate body 1 close to the negative plate 9 is covered with an insulating plate 8, and the insulating plate 8 is fixedly connected to the cover plate body 1. In order to facilitate the flow of gas, the insulating plate 8 is provided with second air holes, the second air holes are arranged in multiple, and the arrangement position of the second air holes corresponds to the arrangement position of the first air holes, so as to facilitate the smooth flow of gas. The both ends of the cover plate body 1 are connected with L-shaped adapters 2, and the cover plate body 1 is further provided with a pole 4. Further, the surface of the third ring table 104 close to the battery 9 is flush with the surface of the cover plate body 1 close to the battery 9.

[0042] The edge of the third ring table 104 is arranged inside the outer edge of the second ring table 105, so as to reserve a certain width of the table surface of the second ring table 105, the bottom surface edge of the rupture disc 6 can be in contact with the table surface of the second ring table 105, the rupture disc 6 can be installed on the second ring table 105, and reliable support for the rupture disc 6 is realized. The edge of the third ring table 104 close to the second ring table 105 is arranged in a spaced manner with the outer edge of the weak part of the rupture disc 6, the size of the outer edge of the weak part of the rupture disc 6 is smaller than the size of the edge of the second ring table 105, the arrangement of the ring table is avoided to block the gas flow, and the gas flow can directly flow to the weak part of the rupture disc 6.

[0043] In an embodiment, as shown in Figure 7 , the top surface of the rupture disc 6 is arranged below the table surface of the first ring table 102. In another embodiment, the top surface of the rupture disc 6 is flush with the table surface of the first ring table 102, as shown in Figure 9 . Alternatively, the top surface of the rupture disc 6 is arranged above the table surface of the first ring table 102, as shown in Figure 8The top surface of the explosion-proof sheet 6 is lower than or flush with the top surface of the first annular platform 102, which increases the welding area of the explosion-proof sheet 6 and the stepped portion, improves the connection strength of the explosion-proof sheet 6 and the cover plate body 1, and reduces the probability of connection failure at the connection position of the explosion-proof sheet 6 and the cover plate body 1. In other words, if the connection of the explosion-proof sheet 6 and the cover plate body 1 fails, it will affect the opening of the weak part of the explosion-proof sheet 6. During thermal runaway of the battery, the heat and pressure inside the battery shell will act on the weak part to open it. If the connection of the explosion-proof sheet 6 and the cover plate body 1 is defective, it will disperse part of the heat and pressure, affecting the explosion of the weak part of the explosion-proof sheet 6.

[0044] Specifically, the explosion-proof sheet 6 is spaced apart from the top surface of the second annular platform 105 and is welded to the connecting side surface 103. In another embodiment, the explosion-proof sheet 6 is in contact with the top surface of the second annular platform 105 and is welded to the connecting side surface 103, or the explosion-proof sheet 6 is welded to the connecting side surface 103 and the second annular platform 105, and the welding reliability of the explosion-proof sheet 6 and the cover plate body 1 is better.

[0045] The explosion-proof sheet 6 includes a main sheet body 603 and a connecting platform 601, as shown in Figures 10 to 12 The connecting platform 601 is arranged around the main sheet body 603. In order to improve the connection reliability, the thickness of the connecting platform 601 is greater than the thickness of the main sheet body 603. The main sheet body 603 is provided with a weak part near the connecting platform 601, which can be a groove 602. The specific thickness of the connecting platform 601 is set according to the actual welding needs. The connecting platform 601 is used to connect with the inner wall of the pressure relief hole 7. In an embodiment, the side surface of the connecting platform 601 is welded to the connecting side surface 103.

[0046] In order to avoid the inflow of electrolyte into the pressure relief hole 7 when the electrolyte is injected through the liquid injection hole 5, the top surface of the protruding portion 101 protrudes from the cover plate body 1, and the top surface of the protruding portion 101 is fixedly connected with the protective patch 3, which covers the pressure relief hole 7 and is used to block the end surface opening of the pressure relief hole 7. In an embodiment, the protective patch 3 is made of plastic.

[0047] The distance H1 between the explosion-proof sheet 6 and the end surface of the negative electrode sheet 9 of the battery cell is in the range of 0.3-10 mm, and the distance H2 between the upper surface of the cover plate body 1 and the explosion-proof sheet 6 is in the range of 0.5-2.5 mm. Specifically, as shown in Figure 4 The distance H2 is the distance between the upper surface of the cover plate body 1 and the upper surface of the connecting platform 601 of the explosion-proof sheet 6. The distance H1 is the distance between the lower surface of the explosion-proof sheet 6 and the end surface of the negative electrode sheet 9 of the battery cell.

[0048] In the description of the present solutions, it needs to be understood that the terms "first", "second" are only used for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly pointing to the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present solutions, the meaning of "multiple" is two or more, unless otherwise explicitly and specifically limited.

[0049] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between the various embodiments can be mutually referred to.

[0050] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery, characterized by, The battery cover plate assembly is connected to the top opening of the battery shell, and the battery cover plate assembly comprises a cover plate body, a relief hole is arranged on the cover plate body, a protruding portion is arranged around the relief hole, and a rupture disc is arranged in the relief hole.

2. The battery of claim 1, wherein, The distance between the rupture disc and the negative plate of the battery cell is H1, and the distance between the upper surface of the cover plate body and the rupture disc is H2, wherein the range of H1 / H2 is 1.5-15.

3. The battery according to claim 1 or 2, characterized in that, A first ring table and a second ring table are arranged on the hole wall of the relief hole, the first ring table and the second ring table are arranged vertically to the center line of the relief hole, the first ring table is higher than the second ring table, the first ring table and the second ring table are connected by a connecting side surface, and the rupture disc is connected to at least the connecting side surface.

4. The battery of claim 3, wherein, The first ring table is lower than the upper surface of the cover plate body.

5. The battery of claim 3, wherein, The top surface of the rupture disc is arranged lower than the table surface of the first ring table. Alternatively, the top surface of the rupture disc is arranged flush with the table surface of the first ring table. Alternatively, the top surface of the rupture disc is arranged higher than the table surface of the first ring table.

6. The battery of claim 3, wherein, The rupture disc is arranged in a spaced manner with the table surface of the second ring table, and the rupture disc is welded on the connecting side surface. The rupture disc is in contact with the table surface of the second ring table, the rupture disc is welded on the connecting side surface, or the rupture disc is welded on the connecting side surface and the second ring table.

7. The battery of claim 3, wherein, A third ring table is further arranged on the hole wall of the relief hole, and the third ring table is lower than the second ring table.

8. The battery of claim 7, wherein, The edge of the third ring table is arranged inside the outer edge of the second ring table, and the rupture disc is in contact with the table surface of the second ring table. The edge of the third ring table is arranged in a spaced manner with the outer edge of the weak portion of the rupture disc.

9. The battery of claim 1, wherein, The top surface of the protruding portion is protrudingly arranged on the cover plate body, a protection patch is fixedly connected to the top surface of the protruding portion, and the protection patch covers the relief hole.

10. The battery of claim 2, wherein, The distance H1 between the rupture disc and the negative plate of the battery cell ranges from 0.3mm to 10mm, and the distance H2 between the upper surface of the cover plate body and the rupture disc ranges from 0.5mm to 2.5mm.

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